US4357203A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Plasma etching of polyimide
Assignee: Intersil Corp
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Filing: 1981-12-30
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Granted: 1982-11-02
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Expires: 2001-12-30
Abstract
Abstract An improvement in the formation of multilayer metallization systems wherein vias are formed in a dielectric insulating layer of polyimide which overlies a layer of metal such as aluminum. In accordance with the invention, the residual film remaining after oxygen plasma etching of the polyimide is efficiently removed by a second plasma etching utilizing a mixture of argon and hydrogen.
Inventors
- 👤 Joseph Zelez
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 18:04
CPC Classifications
H; H10; H10W; H10W20/00; H10W20/01; H10W20/071; H10W20/081; H10P; H10P50/00; H10P50/20; H10P50/28; H10P50/286; H10P50/287
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
46 words
In a method of forming a multilayer metallization system including the step of forming vias in a polyimide dielectric insulating layer overlying a layer of metal by oxygen plasma etching, the improvement comprising plasma etching with a mixture of argon and hydrogen after oxygen plasma etching.
Claim 2
Dependent Claim
46 words
In a method of forming a multilayer metallization system including the step of forming vias in a polyimide dielectric insulating layer overlying a layer of metal by oxygen plasma etching, the improvement comprising plasma etching with a mixture of argon and hydrogen after oxygen plasma etching.
Claim 3
Dependent Claim
28 words
A method in accordance with claim 1, wherein the partial pressures of argon and hydrogen in said mixture are in a ratio from about 2:4 to about 7:2.
Claim 4
Dependent Claim
25 words
A method in accordance with claim 2, wherein the partial pressures of argon and hydrogen in said mixture are in a ratio of about 6:2.
Claim 5
Dependent Claim
13 words
A method in accordance with claim 1, wherein said metal layer is aluminum.
Claim 6
Dependent Claim
37 words
A method in accordance with claim 1, wherein said plasma etching with argon and hydrogen is carried out at a negative potential of from about 800 to about 1,200 volts for from 1 to about 30 minutes.
Claim 7
Dependent Claim
34 words
A method in accordance with claim 1, wherein the polyimide layer is subsequently coated with a second layer of metal to provide contact between the first and second layers of metal in the vias.
Claim 8
Dependent Claim
17 words
A method in accordance with claim 6, wherein the first and second layers of metal are aluminum.
References Cited (Backward Citations)
US4278493A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1985-11-01 | 1986-05-03 | 1986-11-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1989-11-01 | 1990-05-03 | 1990-11-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1993-11-01 | 1994-05-03 | 1994-11-02 | $7700.00 | Window Closed / Lapsed |